Grain dehydrator



A. B. WELTY GRAIIN DEHYDRA'TOR Nov. 12, 1946. 2,410,851

' Filed March 27, 1944 S Sheets-Sheet 1 Nov. 12, 1946. A. B. WELTY GRA IN DEHYDRATOR 5 Sheets-Sheet 2 Filed March 27, 1944 t m mg 4, t 2 a w Ym M m m N m m Patented Nov. 12, .1946

l GRAIN nnnvmm'ron Albert B. Welt y, Moline, 111., assignor to Internampany, a corporation of tional Harvester Co New Jersey.

Application March 27, 1944, Serial No. 528,254

This invention relates to a new and improved grain dehydrator and has for one of its principal objects the provision of, novel means for drying quantities of grain preliminary to storage.

An important object of the present invention is to provide .a portable graindryer which may 1 be readily moved to any desired position.

Another important object of this invention is the provision of a corn dryer, wherein a quantity of corn is so treated that the greater percentage of moisture is removed therefrom.

Storing of corn without spoilage is a big problem to the individual farmer as well as tothose persons.- operating grain elevators. When the corn is picked, the kernels usually contain a high percentage of moisture. mediately shelled from the cobs andstored in a 1 China (Cl. 263-19) If such corn were imtight grain bin, spoilage would begin promptly.

after it has been picked, the corn would be left on the cobs and placed in open corn cribs, so that air could circulate through and cause natural drying of the corn. process, however, re-' quired considerable time, and although there was not much danger of spoilage because the kernels were all opened to the atmosphere, losses did occur. These losses were chiefly caused by rodents or other small animal nesting in the com bins. The danger of fire with the corn in Other and further important objects of the present invention will become apparent from the following specification and accompanying drawings, in which:

- Figure 1 is a perspective view of the portabl rain dehydrator of this invention;

Figure 2 is an end view of the device as shown in Figure 1;

Figure 3 is a sectional view taken on the line 33 of Figure 1;

Figure 4 is a sectional view taken on the line 4-4 of Figure 3 and Figure 5 is a skeleton perspective view of the device indicating heat circulation with arrows.

The' reference numeral Ill indicates generally a chassis or frame upon which is mounted a body H. The frame is carriedby wheels I2. The forward end of the frame I0 is equipped with a hitch l3 which maybe attached to and drawn by a tractor or the like. It is obvious that this grain dehydrator is portable and maybe moved from Howeverywhen the grain dryer is in operation, it is desired to have it remain quite stationary and to this end leg members II are supplied. These legs M are of the extension type, and although they are mounted rigidly at If: on the body I I, they may be extended or retracted by means of-an adjustment l6. V

The travel of shelled corn through the grain dryer requires several mechanical devices and a plurality of'elevators, and to effect an operation of these units an engine. I! is'provided. One of the main functions of the engine is to drive a fan I8 as shown in Figure 4. As best shownin this condition was excessive and also contributed to the losses. 7

Operators of grain elevators employ artificial means for driving the'moisture out of corn and may therefore safely buy shelled corn which has a high moisture content. The price of high moisture corn per bushel is much less than the price of "dried corn per' bushel. It is quite advantageous to corn growers to sell their corn when it is dry rather than accept the low price for moist com.

Figure 1, the internal combustion engine I I imparts rotation to the pulley IS on the crank-shaft '20. It is, of course, understood that power for the grain dryer operating units may be obtained from other means than an internal combustion engine such as an electric motor, a, steam engine,

- or the like. A pulleyj2l is mounted on the fan- It is, therefore, an important object of this in shaft 22 and is operatively joined to the pulley I! by means of a belt 23.

A heating unit, shown at 24, is provided on the frame III to supply the artificial heat needed to drive the moisture from the kernels of grain. The heater 24, shown here, is an voil burner type, and it is obvious that any type of furnace or heater could be employed and still secure the desired dehydration results. A fuel oil tank is shown at 25 for feeding fuel to the oil burner 26. A motor 21, preferably driven by electricity from 3 a power-line 28, drives a pumpwithin the housing 29.

As best shown in Figure-2, supply hopper 3! may be filled by any means such as the trough 32 shown here coming from a large receptacle 33. The hopper 3| is substantially V-shaped and is equipped with an auger lying parallel to the vertex. 'The auger (not shown) is adapted to feed the grain to one end of the hopperwhere it communicates with a supply elevator 34. The grain is then lifted to the top 35 of the elevator 34, and, as best shown in Figure 1, discharges kernels of corn into a hopper-like member 36. A pipe 31 extends longitudinally of the body II and is attached at one end to the hopper 36 at 38, as shown in Figure 1. In the pipe 31 is housed an auger 40 which projects within the hopper 36, as shown in Figure 4,

and extends the entire length of the pipe 31. The

auger 40 is equipped with a central shaft 4| which extends beyond the hopper 36 and beyond the other end of the pipe 31. As the kernels of com are fed to the hopper 36, they are carried by the rotating auger 46 :through the pipe 31.

The holes 3 9, in the bottom of the pipe, permit the corn to drop through into the chamber 42 within the body The corn will continue to drop through this successive series of holes until suchv time as the column formed therebeneath supplies sufficient back pressure to cause the corn to travel pivoted at 49 and which has a handle portion 50 swingable on the arcuate member 5|. In the position shown, the idler pulley 41 has so tightened the belt 44 that it effects a drive between the fanshaft 22 and the shaft 46. However, if the handle 50 of the bell-crank 48 were swung in a rightward or counterclockwise direction, viewing the device as in Figure l, the idler pulley 41 would be withdrawn from contact with the belt 44 and so permit rotation of the shaft 22 without resulting rotation of the shaft 46. Figure 3 shows an enlarged view of the pulley 45 and its shaft 46. From this view it is seen that a bevel pinion gear 41, keyed or otherwise fastened to the end of shaft 46, cooperates with a large bevel gear 48 which is keyed or otherwise fastened to the auger shaft 4|. From this arrangement of pulleys and gears, it will be understood that the engine |1 effects a driving of the fan 8, the auger 40, in addition to supplying a continuously rotating end '43 of the auger shaft 4|. This rotating end 43' is best shown in Figures 1, 2, and 4, and in Fig-' Figure 3 is a cross-sectional view of the chamber 42 of the grain'dryer. As the grain discharges from the pipe 31, it forms a central ridge directly beneath the pipe 31 and from there it tapers downwardly as shown by the lines 68. In operation, the chamber 42 is entirely filled with kernels of corn, and it is the object of this device to heat this column of corn in the chamber 42 and then discharge it from the bottom thereof, whereupon ,parallel with the inclined surface 59 directly above, and similarly, the heat entrances 63, 64, and 65 are substantially parallel with the corn surface line directly above them. As the corn enters the chamber 42, through the openings 39 and the pipe 31,.it is generally cold and relatively moist. As heat is driven upwardly from the plenum chambers 66, 61, and 68, it causes drying of the com. The height of the column of grain in the chamber 42 is predetermined so that the major portion of the heat is utilized. In other words, by the time the heated air has passed through the column of grain it is substantially saturated and approximately at' room temperature. The top of the grain drying chamber is open and the air after passing through the column of grain is discharged through the open top. It is obvious that at different levels within the chamber 42, the corn will be at diflerent temperatures.

. As the corn progresses downwardly, it gets hotter and dryer. The parallelism between the upper surface of the corn and the heat entrances is for the purpose of effecting a-uniformed heating of the corn over the entire width of the dryer.

ures 1 and 2 it is evident that a pulley 50' is keyedgi,

or otherwise fastened to this rotating shaftend 49'.

Several pulleys, namely, 5| 52, and 53, are in a common plane with the pulley 56' and are joined together by means, of a crossed belt 54. The pulley 5| is mounted on shaft 55 and directly drives the grain supply elevator 34. The pulley 52 is mounted on shaft 56 and imparts a drive to a grain discharge elevator 51. The pulley 53. is an idler tightener pulley and is mounted on a stub-shaft 58.

The chamber 42 is rectangular in shape and is well insulated from the atmosphereby thickly insulated walls 43 as shown in Figures 3 and Grain discharge rolls 68 are positioned adjacent the lower portions of each plenum cham-- her. One of these rolls is shown in greater detail in Figure 4. It will be seen that the periphery of the rolls is provided with intermittent pockets 10 so that at no place around the roll is there a continuous cut out portion, or is there a continuous cut-out portion from one end of the roll to the other. The pockets 10 are offset bot'n around and longitudinally of the rolls 69. Returning to Figure 3, it will be obvious that the kernels of corn will fill the pockets 10, and upon rotation of the rolls 63 will permit a discharge of the'kemels at the point 1| at the bottom of the rolls. The size and number of pockets in the rolls are such that the corn is removed at substantially the same rate at which it is fed to the device whereby the hopper is maintained substantially filled and always presents a uniform column of grain of the desired altitude. Partitions 12 are attached to the sides of the several plenum chambers and, in cooperation with similar partitions 13, provide a trough with an opening in the bottom thereof for feeding directly to the pockets 10 within the rolls 69. Fur- V ther, the rolls 69 are partially surrounded with or the like (not shown). The space "H between the rods ll and i8 is to permit the discharge of kernels. The covers id snugly engage the'annular peripheries of the rolls 69 and so prevent to a great degree the passage of hot air from the chamber 52 to a chamber i9 beneath the plenum chambers. Conversely, cold air in the chamber 19 is prevented from into the grain column chamber 2,.

At the time the corn kernels are discharged at the spaces ii beneath the rolls 89, they are very hot and if stored in that condition would tend to take on considerable surface condensation with the result that the corn would be in no better condition for storing than before dehydration.

- It is, therefore, necessary to provide means for bringing the temperature of the corn down after it has been heated and dried preliminary to storing. The chamber 19 includes a COOlillg means. The corn from all four of the rolls 89 is dropped on to a cross-conveyor 89 which extends substantially across the width of the grain dryer. This conveyer 86 is preferably of the canvas type and extends around end rolls 8i and 82 which have centralshafts 83 and M, respectively. Slat rection, as viewed in Figured, and all grain discharged by the rolls 5t will be carried around the end 82 and dropped on a corrugated bottom 87. This corrugated bottom 81 is best shown in Figure 4 and includes peaks 88 and depressions 89.

The nail-like projections 8'6 are adapted to project downwardly within the depressions 89, and as the kernels of corn are dropp d on to the bottom 91 at the point 98, the kernels are carried substantially individually across this corrugated bottom 81 within the depressions 89. The kernels are discharged at the point 9! closely assing upwardly aei ssi shown in Figure 2, is thus prevented from contacting the ratchet teeth and'movement of the ratchet wheel iill is thereby delayed until the pawl iM passes beyond the upper limit of the segment I05. The segment Hi5 may be pivoted about its center I50 and fixed in any desired position within the slotted bracket ill? to effect any rate of ratchet rotation that-is permissible between thelimits of movement of the pitman 91. A second pawl 18 is resiliently held against the bottom of the ratchet wheel lot by means of a spring "19.. This ratchet wheel prevents rearward or counter-clockwise rotation of the ratchet'wheel IUI when the pawl we no longer is engaged with the ratchet teeth. A chain H0 is wrapped around each of the sprockets 95 as well as the sprocket Hi2, an idler sprocket Hi, and the sprocket H2; The sprocket H2 is mounted on the shaft 84 which is a continuation of the shaft for the roll 82 of the cross-conveyor 86. From this it will be evident that drive from the pulley 50 through the pawl IN to the ratchet wheel llii imparts rotation to the rolls 89 as well as the conveyor 80. The idler sprocket iii is mounted on a stub shaft H3 and merely performs the function of maintaining the chain adjacent a discharge auger 92 so that the grain coming down an inclined surface 93 isfed rearwardly to the point where it joins the grain discharge elevator 51.

The rolls $9 have central shaft 96 journaled in the housing which project rearwardly beyond the housing ii asshown in the Figure 2 rear view. Each shaft 95 has a sprocket 95 keyed or otherwise fastened thereto.

It is a requirement of this grain dehydrator that the discharge rolls 59 rotate very slowly and to that end a particular drive is employed. The

pulley is equipped with a crank pin 96 to which is attached a pitman at. It will be evident that as the pulley 56' rotates, the pitman at will reciprocate vertically. The lower end of the pitman is attached at 98 to an arm 99 which is pivmember Edd. This member it is in the form of taut.

As previously stated, the oil burner throws a fuel oil through the tube 30 into a furnace lid which has a dome-like structure 1 55 within which combustion takes place The fan id, as shown in Figure 4, is adapted to take air in at H6 and supply it with a high. velocity so that it is projected downwardly through the opening HT di- 1 atmosphere but as.best shown in Figure 3 is drawn in through an entrance H8 in the bottom of the housing and passes beneath the corrugated bottom Bl of the cooling chamber F9. The air thus drawn in is within a chamber Ht between the bottom plate i20 and the corrugated partition 81. The kernels of corn are passing individually along the corrugations within the depressions 89, thus transferring heat from the dehydrated corn to the incoming air. This performs two functions: (1) that of cooling the finished corn and (2) that of preheating the incoming air to be used in the dehydrating process.

As best shown in Figure 5, after the incoming air has traversed the chamber H9, it enters a substantially triangularly shaped chamber i2! which carries it along the side of the grain dryer 7 housing and thence upwardly through the con duit E22 where it is drawn into the fan l8 by means of the suction created by the fan. From this description, it is seen that the air that is used to directly contact the corn is free from contamination with any exhaust gases inasmuch as the furnace H4; is sealed from the chamber I28 surrounding the furnace.

The exhaust gases formed after combustion of g the oil within the furnace II4 pass upwardly 'which causes the hot exhaust gases to progress circularly and upwardly in the manner indicated by the arrows. It will be obvious that the gases are required to travel through one-half of the cylindrical conduit I25 where it progresses upwardly into a second section I25 of the cylindrical conduit, whereupon it proceeds back around another half revolution and then-up t the third and top section I21 of the cylindrical conduit. This is shown in great detail in Figures 4 and 5; This circulation of exhaust gases contributes greatly to the heating of the chamber I23, thus utilizing more of the combustion heat produced by the oil burner 24 or by any type of fuel or furnace that may be employed. The exhaust gases continue travel upwardly'as at I28 into a second set of heat transfer conduits which surrounds the fan I8. This also contributes high operating efiiciency by the utilization of all heat available. The exhaust gases enter the vertical column I29 and pass through numerous tubes I30 where they congregate in a second vertical column i3I and are discharged into a horizontal tubular member I32. This tubular member I32 is positioned directly beneath the feed pipe 37 and is buried within the column of corn in the chamber 42. Here again the exhaust gases are utilized to their maximum capacities and contribute greatly in preheating the columnof corn in the chamber 62. The tubular member I32 is superposed by an outer tubular member I33. The end of the member I33 is secured to the end wall of the grain dryer at I34. As exhaust gases cool, they tend to condense, and it is therefore necessary to provide a drain for such condensation. The bottom of the tubular member I33 is U- shaped as shown at I35. This lower U-shaped portion of the tube-I33 tapers downwardly toward the rear of the grain drying machine, and at its end communicates with a drain pipe lat which projects through the insulated wall it. The tube I32 terminates at a point short of the end wall, thus permitting the flue gases to come out into the outer tubular member I33 whereupon they are caused to return by contact with the end wall 43 and pass the length of the tube I33, whereupon they are discharged by means of an exhaust fan at I31.

Heat created by the oil burning unit 2 3 is utilized. The in-take air is preheated. The heated air which emerges, from the column of grain from the chamber 42 is substantially room temperature, and the combustion gases pass through numerous heat transfer devices so that the entire grain dehydrator circulation has attained its maximum efflciency.

The grain discharge elevator 51 connects with two discharge spouts I38 and I33. A valve (not shown) can be operated to cause discharging of corn to either of these spouts lll or I39. The spout I33, however, discharges into the which is the supply for the corn to begin its travel through the grain dehydrator. At intervals in the operation of this grain dehydrator, the moisture content of the discharged kernels is tested and, if the content is above some predetermined percentage, thenthe grain is diverted to the spout I38 where it is again dried. If, however, the moisture content is low enough to have good storing qualities, then the grain is discharged through the spout I39 to some desired bin as storage bin. The testing for moisture may be done inseveral ways. The subject grain dryer is adapted to employ a mechanical means to test for moisture content and to that end a pulley I40 is fastened to the shaft 56 and by means of a belt I acts to cause rotation of the pulley I42 which operates a grain testing device (not shown). An idler pulley I43 maintains tension in the belt MI. The details of the moisture testing device, indicated at I44 and driven by the pulley I42, is shown in greater detail in my co-' pending application having Serial No. 528,255 and filed March 27, 1944.

Numerous details of construction may be varied throughout a. wide range without departing from the principles disclosed herein. The subject device has been described as a corn dryer when in fact it may be used successfully for drying other smaller grains with but slight changes in the structures.

The intention therefore is only to limit the invention within the scope of the appended claims.

What is claimed is:

1. In a grain dehydrator, a grain chamber, means for moving grain from the top to the bottom of said chamber, a heating compartment, a furnace within said compartment, 9. fan for blowing air downwardly over said furnace and up through the grain chamber, and means for utilizing exhaust gases from the furnace to preheat the incoming air, said nieans comprising coils of enclosed conduits positioned around said fan.

2. A grain dryer comprising a grain chamber, a grain feed device at the top of said grain chamber, a grain discharge device at the bottom of said chamber, a heating compartment adjacent said grain chamber, a sealed furnace within said heating compartment, a discharge conduit for exhaust furnace gases, said discharge conduit taking a circuitous path around said heating compartment, and fan means for blowing air downwardly through said heating compartment and up through the, grain chamber, a continuation of said discharge conduit circling the fan means.

3. A grain dryer comprising a grain chamber, a grain feed device at the top of said grain chamber, a grain discharge device at the bottom of said chamber, a heating compartment adjacent said grain chamber, a sealed furnace within said heating compartment, a discharge conduit for exhaust furnace gases, said discharge conduit taking a circuitous path around said heating compartment. fan means for blowing air downwardly through said heating compartment and up'through the grain chamber, a continuation of said discharge conduit circling the fan means, and a conduit extending longitudinally through the grain chamber near the top thereof, said conduit joining with the discharge conduit for exhaust furnace gases whereby complete utilization of furnace heat is accomplished.

4. In a grain dryer, 9. grain chamber, means for maintaining said grain chamber constantly filled, said means comprising a means for feeding grain at the top of said chamber and means for removing grain from the bottom of the chamber, said last named means comprising an endless belt conveyer beneath said grain chamber adapted to carrythe grain to its discharge end, a corrugated partition beneath and projecting beyond the discharge end of said conveyer and adapted to receive the grain from the conveyer, projections on said belt conveyer on its under side adapted to run through said corrugations whereby the grain deposited on the corrugated partition is carried in the opposite direction by said projections through said corrugations, a bottom b'eneath and spaced apart from said corrugated partition, and means for drawing air through the space between the corrugated partition and the bottom for preheating the air preliminary to its circulation through the grain chamber, and simultaneously cooling the grain in its travel through the corrugations.

5. In a grain dryer, a grain chamber, means for feeding grain at the top of said chamber and means for discharging grain from the bottom of the chamber, an endless band conveyer beneath said grain chamber discharge means, said endless band conveyer adapted to carry the grain to one side of the grain chamber, a corrugated shelf spaced beneath said conveyer and adapted to receive grain from said endless band conveyer, on the return of the endless band on its under side, projectionson said endless band conveyer adapted to run through said corrugations whereby the grain is carried in the opposite direction by said projections over said corrugations, air-circulating means for said grain chamber, a bottom beneath and spaced apart from said corrugated shelf, and means for drawing air through the space between the corrugated shelf and the bottom for preheating air for the air circulating means and simultaneously cooling the grain in its discharge over the corrugated shelf.

6. A grain dryer comprising a grain chamber, means for feeding grain to the top of said chamber and means for removing grain from the bottom of said chamber, a furnace adjacent said grain chamber, a discharge conduit for furnace combustion gases extending longitudinally of said grain chamber immediately beneath the top thereof, a superposed return conduit for said longitudinally extending discharge conduit, and means for exhausting the combustion gases.

'7. A grain dryer comprising a grain chamber, means for feeding grain to the top of said chambar and means for removing grain irom the bottomof said chamber, a furnace adjacent said a grain chamber, a discharge conduit for furnace combustion gases extending longitudinally of said grain chamber immediately beneath the top thereof, a superposed return conduit for said longitudinally extending discharge conduit, means for exhausting the combustion gases, and a condensate drain for said superposed return conduit.

ALBERT B. WELTY. 

